Porting DOOM to new hardware and software platforms is a fun pastime for many in the hacker scene. [DragonMinded] noticed that nobody had ported the game to the Sega Naomi arcade hardware, and set about doing so herself.
The port builds on work by [Kristoffer Andersen] who built a framebuffer port of DOOM previously. It’s available pre-compiled, complete with the shareware WAD for those eager to load it up on their own Naomi arcade cabinets.
Unlike some limited ports that only give the appearance of a functional version of DOOM, this port is remarkably complete. Loading, saving, and options menus are all present and accounted for, as well as directional sound and even WAD auto-discovery. With that said, there’s only 32 KB of space for save games on the Naomi hardware, so keep that in mind if you find yourself playing regularly.
[Gabe Schuyler] had a frustrating problem when it came to getting into his building’s garage. The RFID access system meant he had to remove his gloves while sitting on his motorcycle to fish out the keytag for entry. He decided to whip up a better solution with less fuss.
His initial plan was to duplicate the keytag and to sew one into his gloves. Purchasing a 125 KHz RFID tag duplicator off eBay, he was able to quickly copy the tag, and create one that worked with his garage’s entry system. While the duplicate tags worked well, they were still too big to easily fit into a glove. Attempts to create a duplicate with a smaller tag failed, too. Eventually, [Gabe] turned up a ring complete with a compatible RFID chip, and was able to duplicate his entry tag onto that. Now, by wearing the ring, he can enter his garage and building with a simple wave of the hand, gloves on or off.
Of course, duplicating an RFID tag is no major hack. As per [Gabe]’s Shmoocon talk on the topic, however, it shows that many buildings are using completely insecure RFID access methods with little to no security whatsoever. Anyone that found an access tag lying on the ground could easily replicate as many as they wanted and enter the building unimpeded. It also bears noting that you can snoop RFID cards from further away than you might expect.
Say what you will about [Thomas Edison], but it’s hard to deny the genius of his self-proclaimed personal favorite invention: the phonograph. Capturing sound as physical patterns on a malleable medium was truly revolutionary, and the basic technology that served as the primary medium of recorded sound for more than a century and built several major industries is still alive and kicking today.
With so much technological history behind it, what’s the aspiring inventor to do when the urge to spin your own phonograph records strikes? Easy — cut them from wood with a CNC router. At least that’s how [alnwlsn] rolled after the “one-percent inspiration” hit him while cutting a PCB with his router. Reasoning that the tracks on the copper were probably about as fine as the groove on a record, he came up with some math to describe a fine-pitch spiral groove and overlay data from a sound file, and turn the whole thing into G-code.
For a suitable medium, he turned to the MDF spoil board used to ship PCB stencils, which after about three hours of milling resulted in a rather hairy-looking 78-RPM record. Surprisingly, the record worked fairly well on a wind-up Victrola. The spring-powered motor was a little weak for the heavy wooden record and needed a manual assist, but you can more or less clearly hear the 40-second recording. Even more surprising was how much better the recording sounded when the steel needle was replaced with a chunk of toothpick. You can check out the whole thing in the video below, and you’ll find the G-code generation scripts over on GitHub.
Is all this talk about reproducing music using wiggly lines confusing you? Woah, there, whippersnapper — check out [Jenny]’s primer for the MP3 generation for the background you need.
Old lab equipment was often built to last, and can give decades of service when treated properly. It’s often so loved that when one part fails, it’s considered well worth repairing rather than replacing with something newer. [Michael] did just that, putting in the work to give his Fluke 8050A multimeter a shiny new display.
The Fluke 8050A is a versatile device, capable of measuring voltage, current, and resistance in addition to decibels at various impedences and conductance, too. The original display doesn’t show some of the finer details so well, so [Michael] elected to improve on that when he installed a new 2.2″ graphical LCD to replace the basic 7-segment LCD that originally came with the hardware.
To achieve the install, the original LCD display module was removed from the chassis. A piggyback device that sits under the Fluke’s microcontroller was then used to break out signals for the new graphical LCD without requiring modification to the meter’s PCB itself. An Atmega32u4 microcontroller then takes in these signals, and then drives the graphical LCD accordingly.
It’s a great hack that makes the old multimeter easier to use, and the new white-on-green display is far kinder on the eyes, too. We’ve seen other multimeters get screen transplants before, too. Of course, if you’re new to the world of segmented LCDs and want to learn more about how they work, [Joey Castillo]’s talk from last year’s Remoticon will get you up to speed!
How can the big box store mix the perfect shade of English Wedgwood right before your eyes? The answer is in highly-concentrated pigments that come in many different sizes up to a whopping five gallons. Now, just imagine the amount of watercolor, acrylic, or other types of paint that could be made by simply scraping the walls of an empty 5-gallon tub, which you know is just getting thrown away with all that usable pigment inside.
The process will likely take the form of an open-source three-roller milling machine, which are commonly used in paint manufacture. Basically you have three rollers that process the pigment and binder, and the mixture is run through as many times as necessary. Although they are fairly simple machines in design, building them to work well requires adherence to precise technical specs.
We can’t wait to see what [technoplastique] comes up with to use for the stainless steel rollers. The rest of the plan involves a Raspberry Pi Pico, one DC motor per roller, a motor shield, and a power supply, but the rollers are pretty crucial. If you have any ideas other than steel rolling pins (the kitchen kind) or pipe couplings (which are too short, anyway), let us know in the comments!
When Astra’s diminutive Rocket 3.3 lifted off from its pad at the Cape Canaveral Space Force Station on June 12th, everything seemed to be going well. In fact, the mission was progressing exactly to plan right up until the end — the booster’s second stage Aether engine appeared to be operating normally until it abruptly shut down roughly a minute ahead of schedule. Unfortunately, orbital mechanics are nothing if not exacting, and an engine burn that ends a minute early might as well never have happened at all.
According to the telemetry values shown on-screen during the live coverage of the launch, the booster’s upper stage topped out at a velocity of 6.573 kilometers per second, well short of the 7.8 km/s required to attain a stable low Earth orbit. While the video feed was cut as soon as it was clear something had gone wrong, the rigid physics of spaceflight means there’s little question about the sequence of events that followed. Without the necessary energy to stay in orbit, the upper stage of the rocket would have been left in a sub-orbital trajectory, eventually reentering the atmosphere and burning up a few thousand kilometers downrange from where it started.
Of course, it’s no secret that spaceflight is difficult. Doubly so for startup that only has a few successful flights under their belt. There’s no doubt that Astra will determine why their engine shutdown early and make whatever changes are necessary to ensure it doesn’t happen again, and if their history is any indication, they’re likely to be flying again in short order. Designed for a Defense Advanced Research Projects Agency (DARPA) competition that sought to spur the development of cheap and small rockets capable of launching payloads on short notice, Astra’s family of rockets have already demonstrated unusually high operational agility.
Astra, and the Rocket 3.3 design, will live to fly again. But what of the payload the booster was due to put into orbit? That’s a bit more complicated. This was the first of three flights that were planned to assemble a constellation of small CubeSats as part of NASA’s TROPICS mission. The space agency has already released a statement saying the mission can still achieve its scientific goals, albeit with reduced coverage, assuming the remaining satellites safely reach orbit. But should one of the next launches fail, both of which are currently scheduled to fly on Astra’s rockets, it seems unlikely the TROPICS program will be able to achieve its primary goal.
So what exactly is TROPICS, and why has NASA pinned its success on the ability for a small and relatively immature launch vehicle to make multiple flights with their hardware onboard? Let’s take a look.
With Editor-in-Chief Elliot Williams enjoying some time off, Managing Editor Tom Nardi is flying solo for this special edition of the Hackaday Podcast. Thanks to our roving reporter Jenny List, we’ll be treated to several interviews conducted live from EMF Camp — a European outdoor hacker camp the likes of which those of us in the United States can only dream of. After this special segment, Hackaday contributors Al Williams and Ryan Flowers will stop by to talk about their favorite stories from the week during what may be the longest Quick Hacks on record. There’s a few extra surprises hidden in this week’s program…but if we told you everything, it would ruin the surprise. Listen closely, you never know what (or who) you might hear.